Colorectal cancer (CRC) is the second-leading cause of cancer death in the United States. Screening for CRC reduces mortality and is widely recommended for all adults starting at age 50, yet over 35% of Americans remain unscreened. To address the multiple barriers to CRC screening (patient, clinician, and system), our team developed mPATH-CRC (mobile PAtient Technology for Health-Colorectal Cancer), a patient-friendly iPad program used by individuals immediately before a routine primary care visit. mPATH-CRC is a CRC screening decision aid that helps patients make a screening decision, allows patients to ?self-order? a CRC screening test, and minimizes provider and system barriers. After the visit, mPATH-CRC automatically sends patients who choose to be screened supportive text messages at key times to help them complete their chosen test. In our recently completed randomized controlled trial of 450 diverse patients (R01CA178941), mPATH- CRC doubled the proportion of patients who completed CRC screening. To fully realize mPATH-CRC's potential to decrease CRC mortality, the program now must be implemented in primary care practices in a way that encourages routine and sustained use. However, while hundreds of mobile health (mHealth) tools have been developed in recent years, the optimal strategies for implementing and maintaining mHealth interventions in clinical practice are unknown. We have developed a ?high touch? mHealth implementation strategy based on our prior research and guided by the Technology Acceptance Model and the Dynamic Sustainability Framework. Our strategy leverages evidence-based elements including clinic champions, facilitation, regular data feedback, follow-up training, and adaptation. Our team now proposes to compare the results of the ?high touch? strategy to a ?low touch? strategy using a Type III hybrid study design and incorporating mixed methods to evaluate implementation, maintenance, and effectiveness of mPATH-CRC in a diverse sample of community-based practices. The Specific Aims of the proposal are to: 1) in a cluster-randomized controlled trial of 28 primary care clinics, compare the implementation outcomes of a ?high touch? evidence-based mHealth implementation strategy with a ?low touch? implementation strategy; 2) in a nested pre-post study, estimate the effect of mPATH-CRC on completion of CRC screening within 16 weeks of visit; and 3) determine the factors that facilitate or impede the maintenance of mHealth interventions like mPATH-CRC by surveying and interviewing clinic staff and providers as part of a mixed-methods analysis. This project could decrease CRC morbidity and mortality by translating our evidence-based CRC-screening intervention into community practice, directly addressing the goals of Healthy People 2020 and the National Cancer Moonshot. Importantly, completion of these aims will yield essential information for successful implementation of other technology- mediated interventions in primary care settings, addressing a current gap in knowledge.